New benchmark aims to break 4pm fix hegemony

Siren uses 20-minute trade window in a bid to combat fears of manipulation


A new upstart has joined the foreign exchange benchmark fold. Siren, which began trading in January, is hoping to challenge the iron grip that the WM/Refinitiv 4pm fix has on the spot market.

Siren differs from the 4pm fix by using a longer observation window for trades. This has a twofold effect, its backers claim. One, the benchmark will be harder to manipulate. Two, it will be less susceptible to market impact, which will mean tighter prices for users such as pension funds.

One hedging

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